Exam Question
(a) What are the factors which determine the synchronous speed of a motor?
(b) Three conductors fitted side by side in the stator of a salient-pole alternator. Each generates a maximum voltage of 200V (sinusoidal). The angle subtended at the centre of the stator between adjacent conductors is 20 electrical degrees. If the three conductors are connected in series, find:
(a) The r.m.s. value of the effective voltage and
(b) The 'breadth factor' Using the theory that is the basis of this problem, give one reason why three-phase current has been introduce (10)